The present invention generally relates to N-alkyl ammonium acetonitrile compounds useful in applications such as bleaching and cleaning and particularly in the form of substantially solid sulfate, bisulfate, mixtures thereof, or tosylate salts.
Peroxy compounds are effective bleaching agents, and compositions including mono- or di-peroxyacid compounds are useful for industrial or home laundering operations. For example, U.S. Pat. No. 3,996,152, issued Dec. 7, 1976, inventors Edwards et al., discloses bleaching compositions including peroxygen compounds such as diperazelaic acid and diperisophthalic acid.
Peroxyacids (also known as xe2x80x9cperacidsxe2x80x9d) have typically been prepared by the reaction of carboxylic acids with hydrogen peroxide in the presence of sulfuric acid. For example, U.S. Pat. No. 4,337,213, inventors Marynowski et al., issued Jun. 29, 1982, discloses a method for making diperoxyacids in which a high solids throughput may be achieved.
However, granular bleaching products containing peroxyacid compounds tend to lose bleaching activity during storage, due to decomposition of the peroxyacid. The relative instability of peroxyacid can present a problem of storage stability for compositions consisting of or including peroxyacids.
One approach to the problem of reduced bleaching activity of peroxyacid compositions has been to include activators of hydrogen peroxide or an active oxygen source. U.S. Pat. No. 4,283,301, inventor Diehl, issued Aug. 11, 1981, discloses bleaching compositions including peroxygen bleaching compounds, such as sodium perborate monohydrate or sodium perborate tetrahydrate, and activator compounds such as isopropenyl hexanoate and hexanoyl malonic acid diethyl ester.
Other examples of activators include tetraacetyl ethylenediamine (TAED), nonanoyloxy benzene-sulfonate (NOBS), and nonanoylglycolate phenol sulfonate (NOGPS). NOBS and TAED are disclosed, for example, in U.S. Pat. No. 4,417,934, Chung et al., and NOGPS is disclosed, for example, in U.S. Pat. No. 4,778,618, Fong et al., the disclosures of which are incorporated herein by reference.
Thus, U.S. Pat. No. 4,778,618, Fong et al., issued Oct. 18, 1988 provides novel bleaching compositions comprising peracid precursors with the general structure 
wherein R is C1-20 linear or branched alkyl, alkylethoxylated, cycloalkyl, aryl, substituted aryl; Rxe2x80x2 and Rxe2x80x3 are independently H, C1-20 alkyl, aryl, C1-20 alkylaryl, substituted aryl, and N+R3xcex1, wherein Rxcex1is C1-30 alkyl; and where L is a leaving group which can be displaced in a peroxygen bleaching solution by peroxide anion. U.S. Pat. Nos. 5,182,045, issued Jan. 26, 1993, and 5,391,812, issued Feb. 21, 1995, inventors Rowland et al. are similar, but are polyglycolates of the Fong et al. monoglycolate precursors, or activators.
U.S. Pat. No. 4,915,863, issued Apr. 10, 1990, inventors Aoyagi et al., discloses compounds said to be peracid precursors that have nitrile moieties. U.S. Pat. No. 5,236,616, issued Aug. 17, 1993, inventors Oakes et al., discloses compounds said to be cationic peroxyacid precursors that have nitrile moieties. These nitrile containing activators do not contain a leaving group, such as the Fong et al. leaving groups, but instead include a quaternary ammonium group suggested as activating the nitrile and said, upon reaction or perhydrolysis in the presence of hydrogen peroxide, to generate a peroxy imidic acid as bleaching species. The Aoyagi et al. activators include an aromatic ring, which tends to cause fabric yellowing.
German patent application P4431212.1, published Mar. 7, 1996 describes production of quaternized glycinonitriles in the form of stable aqueous solutions.
New peroxygen activators that provide excellent bleaching and that can be formulated for liquid or solid compositions remain desirable for applications such as laundry and household bleaching and cleaning.
In one aspect of the present invention, nitrites are provided in substantially solid form having the structure of Formula I 
wherein A is a saturated ring formed by five atoms in addition to the N1 atom, the five saturated ring atoms being four carbon atoms and a heteroatom, the substituent R1 bound to the N, atom of the Formula I structure including either (a) a C1-24 alkyl or alkoxylated alkyl where the alkoxy is C2-4, (b) a C4-24 cycloalkyl, (c) a C7-24 alkaryl, (d) a repeating or nonrepeating alkoxy or alkoxylated alcohol, where the alkoxy unit is C2-4, or (e) xe2x80x94CR2R3Cxe2x89xa1N where R2 and R3 are each H, a C1-24 alkyl, cycloalkyl, or alkaryl, or a repeating or nonrepeating alkoxyl or alkoxylated alcohol where the alkoxy unit is C2-4.
The Formula I compounds have a quaternary nitrogen atom (N1), requiring the presence of at least one counterion (Y) to be associated therewith, which is illustrated in Formula I as xe2x80x9cYxe2x8ax96,xe2x80x9d but as understood can be monovalent, or multivalent. Y includes counterions, or organic and inorganic anions, such as chloride, bromide, nitrate, alkyl sulfate, bisulfate, sulfate, tosylate, and mesylate. Especially preferred are methyl sulfate, sulfate, bisulfate, tosylate, and mixtures thereof. Z will be in the range of 0 to 10. These compounds, or salts, are particularly well suited to granule bleaching and cleaning compositions.
The nitriles with the Formula I structure are particularly useful when formulated as compositions that include a source of active oxygen, and these compositions provide excellent bleaching in alkaline solutions.
Preferred embodiments include lower alkyls substituted at the N1, e.g. N-methyl morpholinium acetonitrile, N-ethyl morpholinium acetonitrile, N-butyl morpholinium acetonitrile, which are illustrated by Formula II (with xe2x80x9cnxe2x80x9d preferably being 0 to 24 and where xe2x80x9cYxe2x80x9d is one of the above described counterions). 
A particularly preferred embodiment is an N-methyl morpholinium acetonitrile salt where xe2x80x9cnxe2x80x9d of Formula II is 0. Particularly preferred salts are bisulfate, sulfate, mixtures thereof, and tosylate, which have a substantially reduced hygroscopicity, even in amorphous form, and are useful as crystals, in amorphous form, or when in the form of flowable granules. For example, the preferred bisulfate, sulfate, and mixed bisulfate-sulfate salts may be prepared by heating alkyl sulfate precursor salts in an acidic aqueous solution.
Compositions including these nitrites are useful, for example, in laundry products, such as bleaching additives, detergents, detergent boosters, detergents with bleach, bleaches, bleaching aids, stain removers, and spot treatment products such as stain removers, prewash and presoak laundry aids. Among the advantages derived from such compositions are improved cleaning, stain removal, spot removal, whitening, and brightening of treated articles.